noisy locking rear differential 2002

[xsidewinder]

My the rear end on my 02 4x4 with 85k miles has been making noise for a little while and seems to getting louder. Any body have any experience with this? I was told if I change the rear end grease it would quiet down and should take care of the problem. But I am a little sceptical of that. thanks Rick

[2000CAYukon]

Originally Posted by xsidewinder

My the rear end on my 02 4x4 with 85k miles has been making noise for a little while and seems to getting louder. Any body have any experience with this? I was told if I change the rear end grease it would quiet down and should take care of the problem. But I am a little sceptical of that. thanks Rick

How long has it been since it was changed? Has it ever been changed?

//2000CAYukon

[xsidewinder]

No I have not changed it, that is one of my concerns. I do not want to drain it and change it if at $30 quart (x2.75 quarts) for synthetic oil plus the gasket if it will not eradicate the problem. thanks Rick

[MT-2500]

Originally Posted by xsidewinder

My the rear end on my 02 4x4 with 85k miles has been making noise for a little while and seems to getting louder. Any body have any experience with this? I was told if I change the rear end grease it would quiet down and should take care of the problem. But I am a little sceptical of that. thanks Rick

Try to describe the noise.
All speeds?
Coasting or on a pull or all time..
Rubbing or a rough bearing or a whine?
Does the noise change with acceleration?
http://www.differentials.com/install.html

[2000CAYukon]

Originally Posted by xsidewinder

No I have not changed it, that is one of my concerns. I do not want to drain it and change it if at $30 quart (x2.75 quarts) for synthetic oil plus the gasket if it will not eradicate the problem. thanks Rick

Well in my book, 85K is a long time even for synthetic (but then again I am a maintenance freak).

Where are you buying your gear oil? My local Kragens sell Mobil 1 75W90 Synthetic for 10.99 a qt.

The other reason to pull the diff cover is to look at the magnet for metal fragments.

//2000CAYukon

[scrapdaddy]

there should be a drain plug on the bottom of your rear end i have a 02 and it has one that would save on buying the gasket

[xsidewinder]

It seems to be noisy when coasting, but has a slight clunk when accelerating from a dead stop. reminds me of a noise when axle bearings are bad. But the axle bearings shouldn't be bad at 85K? When I bought it new I took it back to the dealer because I thought the rear end was awful noisy and clunky but they assured me this was normal for a locking diff. thanks Rick

[MT-2500]

Originally Posted by xsidewinder

It seems to be noisy when coasting, but has a slight clunk when accelerating from a dead stop. reminds me of a noise when axle bearings are bad. But the axle bearings shouldn't be bad at 85K? When I bought it new I took it back to the dealer because I thought the rear end was awful noisy and clunky but they assured me this was normal for a locking diff. thanks Rick

Go threw the link posted. If noise changes and noise on deceleration or coast.
The best I got from it would be pinion bearings.
Clunk on start may be drive line/ u joints/ transfer case/ mounts.
It may be time for a rear end bearing inspection.
Check the oil for metal and feel pinion yoke for slack or being rough turning.



Tech Information
Diagnosing Driveline Problems
Diagnosing Noise

Whirring noise only while decelerating at any or all speeds is most likely caused by bad pinion bearings or loose pinion bearing preload, and almost never by bad ring and pinion gears.

A howl or whine during acceleration over a small or large speed range is usually caused by worn ring and pinion gears or improper gear set up.

Rumbling or whirring at speeds over about 20 mph can be caused by worn carrier bearings. The noise may change while turning.

Regular clunking every few feet may indicate broken ring or pinion gears.

Banging or clunking only on corners can be caused by broken spider gears, lack of sufficient positraction lubrication, or worn positraction clutches.

Rumble while turning may indicate bad wheel bearings.

A steady vibration that increases with the vehicle’s speed can be caused by worn u-joints or an out of balance driveshaft.

Clunking only when starting to move or getting on and off the gas might be loose yokes, bad u-joints or worn transfer case or transmission parts